Carbon Flashcards

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1
Q

What is the biological pump?

A
  • Sequestration of CO2 to oceans by phytoplankton
  • Float on surface of oceans to access sunlight for photosynthesis
  • Carbon transferred from atmosphere into phytoplankton
  • Carbon passed up food chain by consumers where it is then released back into the atmosphere
  • Most carbon is cycled in surface waters this way
  • Only 0.1% of carbon reaches sea floor through decomposition and sedimentation
  • Phytoplankton sequester over 2billion metric tonnes of CO2 annually to the deep ocean
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2
Q

What is the carbonate pump?

A
  • Actively moves CO2 from atmosphere into the ocean store
  • Ocean is usually at high temperature and low pressure
  • Many marine organisms use calcium carbonate to build their outer shells/skeletons
  • When these organisms die, they will sink to the sea floor and their shells will dissolve, dissolving the CO2 with it into the ocean
  • The dissolved CO2 circulates around the planet in currents for up to 500 years
  • Any shells that do not dissolve build up on the bottom of the sea floor, forming limestone
  • Intermediate and deep ocean store around 37,100Gt
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3
Q

What is the physical pump?

A
  • Based on global circulation of water
    1. Moves carbon compounds to different parts of the ocean in downwelling and upwelling currents
    2. Downwelling occurs in parts of the ocean where cold, denser water sinks (+ more salinity), such as the poles
    3. These currents bring dissolved carbon dioxide down to the deep ocean.
    4. Once there, it moves in slow-moving deep ocean currents, staying there for hundreds of years (around 500).
    5. Eventually, these deep ocean currents, part of the thermohaline circulation, return to the surface by upwelling.
    6. The cold deep ocean water warms as it rises towards the ocean surface and some of the dissolved carbon dioxide is released back into the atmosphere
    7. CO2 concentration is 10% higher in the deep ocean that at the surface
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4
Q

How does ocean and terrestrial photosynthesis regulate composition of atmophere?

A
  • Photosynthesis requires CO2 to occur
  • Therefore, oceanic and terrestrial autotrophs absorb CO2 from the atmosphere so it enters the biosphere of the organism
  • Here, the CO2 is either released back into the atmosphere, used in metabolic processes or becomes part of a consumers biomass if the organism is eaten and used to synthesis their biological molecules
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5
Q

How is soil health influenced by stored carbon?

A
  • Soil health depends upon the the amount of carbon stored in the soil
  • Carbon is the main component of soil organic matter and helps to give soil its moisture-retention capacity, its structure and fertility
  • Organic carbon is concentrated in the surface layer of the soil
  • A healthy soil has a large surface reservoir of available nutrients which, in their turn, condition the productivity of ecosystems
  • All this explains why even a small amount of surface soil erosion can have such a devastating impact on soil health and fertility
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6
Q

What factors affect carbon sequestration in soils?

A
  1. Climate
  2. Soil type
  3. Management or use of soils
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7
Q

How does climate affect carbon sequestration into soils?

A
  • Rapid decomposition occurs at higher temperatures or under water logged conditions
  • Places with high rainfall or a hotter climate have an increased potential soil carbon store
  • Arid soils can only store 30tonnes per hectare compared with 800 tonnes per hectare in cold regions
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8
Q

How does management and use of soils affected carbon sequestration?

A
  • Since 1950 soils have lost 40-90billion gigatons of carbon through cultivation and disturbance
  • Current rates of carbon loss due to land use change are 1.6billion gigatons of carbon per year
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9
Q

How does soil type affect carbon sequestration?

A

-Clay rich soils have a higher carbon content than sandy soils as clay protects carbon from decomposition

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10
Q

What is energy security?

A

Being able to access reliable and affordable energy sources, either domestic or from ‘friendly’ overseas countries

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11
Q

Urban energy consumption:

A
  • Over half of the world’s population now live in cities
  • They consume 75% of world’s energy and produce 80% of its GHGs
  • London generates 1.7million tonnes of carbon per year, which is 1.8tonnes per capita
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12
Q

Rural energy consumption:

A
  • In rural Peru, a national programme was launches where electricity was made available to 500,000 people in villages between 2006 and 2015 through the use of solar panels
  • This allowed people to charge phones, power lights and TVS as well as extend the working day
  • Increased productivity has allowed extra processing of cereals, meats, cocoa and wood
  • This has boosted incomes and raise rural living standards
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13
Q

Why does energy consumption differ between countries?

A
  1. Physical availability
  2. Technology
  3. Cost
  4. Economic development
  5. Environmental priorities
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14
Q

How does physical availability affect energy consumption?

A
  • Imported energy requires transport which adds onto the overall cost for the consumer
  • Rising costs are likely to decrease consumption
  • Domestic energy can be difficult to access and requires expensive technology
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15
Q

How does climate affect energy consumption?

A
  • Very high levels of consumption in North America, Middle East and Australia reflect the extra energy needed to make extremes of hot and cold more comfortable
  • Compared to places like France that have a more temperate climate, less energy needs to be consumed for technology such as AC and Central Heating year round
  • Dubai, Middle East summer temperatures reach around 40*C but are still hot year round
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16
Q

How does cost affect energy consumption?

A
  • Cost includes physical exploitation, processing and delivery to consumer
  • Relatively low energy costs many be expected to boost consumption
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17
Q

How does economic development affect energy consumption?

A
  • Same energy cost may be perceived as expensive in one country and acceptable in another
  • Public perception will depend very much on the level of economic development and standard of living
  • The higher these are, the less sensitivity to energy cost
  • Developed countries, therefore, have relatively high levels of energy consumption
  • Energy needs to fuel domestic appliances, transport, etc.
  • Also if country, notably China, is going through rapid economic development then energy consumption is going to be high for a period of time in order to keep up with demand
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18
Q

How do environmental priorities affect energy consumption?

A
  • Out of concern for environment in general and about carbon emissions in particular a government may not take a cheapest route to meets its energy needs
  • Wind turbines, solar panels and other renewables can be more expensive, especially due to their lower efficiency
  • Therefore the cost of green energy could have a slightly depressing impact on consumption
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19
Q

Energy Consumption Case Study: USA vs France

A
  1. USA’s energy consumption almost 10 times higher than France’s
  2. USA is at 2224mtoe compared to 243mtoe for France
  3. USA’s energy consumption is 3000kge higher than France’s
  4. Only 50% of France’s energy comes from fossil fuels compared to 80% for the USA
  5. Only 10% of USA’s energy comes from renewables and 8% from nuclear
  6. In comparison, 10% of France’s energy comes from renewables and 40% from nuclear
  7. France’s population is 66.9million (2018) compared to the USA’s population of 327.2million (2018)
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20
Q

Why does France have a lower energy consumption than the USA?

A
  1. Much smaller population
  2. Less major cities to power
  3. USA has higher GDP per capita
  4. USA experiences extreme heat and cold
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21
Q

What is energy mix?

A

Proportion of each primary resources a country uses per year. These resources may be domestic or imported

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22
Q

What is the UK’s energy mix?

A
Coal and Oil: 1%
Natural Gas: 38%
Wind: 20%
Biomass: 12%
Solar: 6%
Nuclear: 19%
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23
Q

What factors affect energy mix?

A
  1. Geopolitical links e.g. Gazprom
  2. Financial cost of each energy option
  3. National and regional policies on climate change e.g. Paris Climate Change Agreement 2015, UK National Policy to band diesel cars by 2035
  4. Energy needs based on economic development and lifestyle e.g. USA has high demand so uses fossil fuels. On other hand, USA has funds to invest into efficient renewable technology
  5. Availability of primary resources within the country, as well as their access to technology to extract the resources e.g. Russia exports 80% of its natural gas to Europe
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24
Q

Norway Energy Security Case Study:

A
  • Norway is very energy secure
  • Norsk Hydro runs over 600HEP sites, which supplies 97.5% of Norway’s renewable electricity
  • Because Norway is mountainous with steep valleys and plentiful rainfall, HEP is the natural energy choice
  • Much of the oil and natural gas in Norway’s natural waters is exported
  • HEP costs are low once capital investment is complete
  • However, transfer of electricity from HEP stations in remote regions to urban populations and isolated settlements is expensive
  • Norwegian government prevents foreign companies from owning any primary energy source sites, so they are energy secure for the future and have the potential to become a major exporter
  • Norway is the third largest exporter of hydrocarbons
  • In 2015, Norway committed to a 40% reduction in domestic GHG emissions by 2030
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25
Q

UK Energy Security Case Study:

A
  • Not very energy secure
  • Was one of the leading countries in energy in the 1950s to 70s
  • UK heavily depended on coal from Yorkshire, Derbyshire and Nottinghamshire
  • It was also among global leaders in nuclear technology
  • North Sea reserves became a ‘secure’ alternative to dependency on Middle Eastern oil
  • North Sea oil is expensive to extract so if global prices fall it becomes less viable
  • Stocks of North Sea oil and gas are declining which is forcing the UK to import more
  • 150 years worth of coal reserves left in UK but current technology and environmental policy makes its extraction unrealistic and expensive
  • Technology exists for ‘clean’ coal (absorbing CO2) but coal has lost is political support
  • Privatisation of UK’s energy supply industry in the 1980s means overseas countries decide which energy sources are used to meet UK demand, they buy primary energy on international markets
  • Increase in nuclear technology and renewables
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26
Q

OPEC as an energy player:

A
  • Organisation of the Petroleum Exporting Countries
  • Made up of 12 member countries in which own 2/3s of world’s oil reserves between them
  • OPEC in a position to control amount of oil and gas entering the global market
  • Also able to set prices of both commodities
  • Been accused of holding back production in order to drive up oil prices
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27
Q

TNCS as energy players:

A
  • Gazprom, BP, Total, etc.
  • Nearly half of top 20 oil companies are state owned so very much under government control
  • Companies involved in exploring, extracting, transporting, refining and producing petrochemicals
28
Q

Energy companies as energy players:

A
  • Companies that convert primary energy into electricity then distribute it
  • Most companies are involved in both the distribution of both gas and electricity
  • Have considerable influence when it comes to setting consumer prices and tariffs
29
Q

Consumers as energy players:

A
  • Create the demand
  • Most influential consumers are transport, industry and domestic users
  • Purchasing choices are often based on price in a competitive led market
  • Consumers are largely passive when it comes to fixing energy prices
30
Q

Governments as energy players:

A
  • Can play a number of different roles
  • Can influence sourcing of energy for geopolitical reasons
  • Meet international obligations, securing energy supplies for nation’s present and future and supporting country’s economic growth
  • Regulation role of private companies and setting environmental priorities
31
Q

What are forms of renewable energy?

A
  1. Nuclear power
  2. Wind power
  3. Solar power
32
Q

What is Hinkley Point C?

A
  • £18billion project involving nuclear power
  • Will provide energy for 60 years and create 25,000 jobs
  • Involves French state owned EDF and China General Nuclear
33
Q

What is Hornsea Project 1?

A
  • 190m high wind turbines
  • Will eventually provide power for 1million homes once completed
  • 121km off the coast of Yorkshire
  • Will create 2000 construction jobs
34
Q

What is Chapel Lane Solar Farm, Christchurch?

A
  • Cost £50million
  • Covers area equivalent to 175 football pitches
  • UK’s largest solar panel farm serving 60,000 homes
  • That’s 75% of the homes in Bournemouth
35
Q

Pros of solar panels:

A
  1. Low maintenance costs, can be maintained for as little as $300 a year
  2. Don’t produce GHGs so have a small carbon footprint
  3. Effective in low income countries
  4. Flexible and modular
36
Q

Cons of solar power:

A
  1. Production off solar panels produces emissions through mining of rare earths required
  2. Only work in certain parts of the world/ at certain times of the year
  3. Needs more research and development especially in storage methods
  4. Can consume productive farmland which some will argue needs to be used for farming at a time where food costs are rising
37
Q

Pros of wind power:

A
  1. Zero carbon emissions
  2. Low operating costs once installed
  3. Efficient use of land space
38
Q

Cons of wind power:

A
  1. Affect aesthetics of an area
  2. Incredibly expensive to install
  3. Heavily dependent on wind so not always reliable
39
Q

Pros of nuclear power:

A
  1. Can be reprocessed and reused and so is recyclable, reducing wasted energy
  2. No GHG emissions
  3. High efficiency- has the capacity to meet city and industrial needs with just one reactors
  4. A relatively small amount of Uranium can be used to power a 1000MW electric plant, providing enough energy to power a city of about half a million people
  5. Low operational costs
40
Q

Cons of nuclear power:

A
  1. Environmental impacts can be detrimental if nuclear waste isn’t disposed of properly
  2. Disastrous if things go wrong e.g. Chernobyl 1986 (technology is better now)
  3. Cost of construction and initiating are highly expensive
  4. Technology involved is complex and therefore its use it only an option for developed nations
41
Q

UK’s Changing Energy Mix: Case Study:

A

-UK’s reliance on fossil fuels is falling and there are plans to close all traditional coal fired power stations by 2025
-60% of the UK’s energy is imported, making it energy insecure
In order to reduce carbon emissions and create a more energy secure future, the UK is committed to reducing the economy’s reliance on fossil fuels by:
-Increasing renewable energy, especially wind and solar
-Developing a new generation of power stations e.g. Hinkley Point C
-Reduce energy use through technology such as LED light bulbs
-Recycling energy that would normally be wasted (nuclear)

42
Q

What are the causes of ocean acidification?

A
  • During acidification, carbonic acid reacts with carbonate ions in the water to form bicarbonate
  • Ocean acidification has lowered the pH of the ocean by about 0.1
  • This means that the ocean is now 30% more acidic that it was in 1750
  • The oceans have absorbed between a third and a half of the CO2 humans have released into the atmosphere since about 1850
43
Q

What threats does ocean health pose to human wellbeing?

A
  • The decline in ocean health caused by acidification and bleaching is resulting in changes to marine food webs
  • In particular, fish and crustacean stocks are both declining and changing their distributions
  • Such changes are being particularly felt by developing countries
  • The FAO estimates that fishing supports 500 million people, 90% of whom live in developing countries
  • Millions of fishing families depend on seafood for income as well as food.
  • Seafood is also the dietary preference of some wealthier countries, notably Iceland and Japan.
  • Aquaculture is on the rise, but its productivity is also being affected by declining pH values and rising temperatures
  • Countries that rely on marine tourism, such as the Maldives and Seychelles are also under threat as coral reefs are dying
44
Q

Why is there uncertainty surrounding future atmospheric CO2 levels and climate warming?

A
  1. Human Factors
  2. Feedback mechanisms
  3. Physical factors
45
Q

What human factors making the future for emissions uncertain?

A

Economic growth:
-After economic crashes there is an expectation that there’ll be a rise in emissions during recovery of global GDP
-Fortunately, in the 2008 financial crash, emissions fell to 1% by 2012-13 from 4%
-Although total emissions before this still experienced a record high
Energy source:
-Energy consumption grew by 2% between 2008-2014
-However, renewables made up two thirds of the increase in electricity production so there were still less emissions
Population change:
-Increasing affluences means growing middle class
-This could mean an extra billion consumers by 2050
-Changing diets and increase disposable income for cars and technology are likely to increase emissions
Advancement in renewable technologies

46
Q

What physical factors create uncertainty for future emissions?

A
  • Oceans and forests act as carbon sinks
  • Their response to increased GHG emissions and higher temperature will continue to affect the climate for hundreds of years
  • Overall, the amount of forested land is on a global decline
  • Natural variations in climate, such as Milankovitch cycles, sun spots and long-term ENSO cycles can also create uncertainty when prediction future effects of climate change
  • If emissions were stopped, some effects of GHGs would immediately reduced but others could take centuries to be rebalanced by Earths systems
47
Q

What is a tipping point?

A

A critical threshold whereby a carbon sink could become a carbon source

48
Q

What is the forest die back tipping point?

A
  • Rainfall in the amazon basin is largely recycled from moisture within the forest
  • If the rainforest is subject to drought, trees die back
  • A tipping point can be reached when the level of die back actually stops the recycling of moisture, resulting in further die back
  • This reduces the forests ability to act as a carbon sink and leaves it more vulnerable to forest fires
49
Q

What is the Thermohaline circulation tipping point?

A
  • Melting of ice sheets release large amounts of freshwater into the ocean
  • This blocks and slows down the belt of warm water from the Tropics to Britain
  • This will affects where CO2 is absorbed and released, and in what quantities
  • The warming of oceans will also see more CO2 being released as warm waters have a much smaller ability to hold CO2
50
Q

What are two positive feedback mechanisms that make future emissions uncertain?

A

Peatlands:
-Warming causes peat to dry out as water tables fall
-Increases decomposition rates and releasing methane
-Methane causes further warming leading to more peat drying out
-A warming of 4*C causes a 40% loss of soil organic carbon from shallow peat and 86% from deep peat
Permafrost:
-The melting permafrost releases CO2 and methane which was trapped within it
-Release of more GHGs causes further planetary warming which releases more gas

51
Q

What are the adaptation strategies for a changed climate?

A
  1. Water conservation and management
  2. Land use panning and flood risk management
  3. Resilient agricultural systems
  4. Solar radiation management
52
Q

Water conservation and management:

A
  • Israel has a range of strategies to manage its limited supplies of freshwater
  • Smart irrigation
  • Recycling sewage water for agricultural use
  • Reducing agricultural consumption and importing water in food as virtual water
  • Adopting stringent conservation techniques
  • Managing demand by charging ‘real value’ prices for water to reflect cost of supply and of ecosystem management
53
Q

Land use and flood management:

A
  • Increased risk of flooding due to changing precipitation patterns
  • Land use zoning is used where floodplain development is limited to low impact things like playing fields and parks
  • Low cost approach to flood management
  • Infiltration can still occur naturally and surface run off is reduced along with the wider risk of flooding
  • Focused land use planning can be used for renewable energy, by designating areas that can be converted to generate energy
  • California’s Desert Renewable Energy Conservation Plan 2019 crafted a plan across 10million acres of desert on federal public lands
  • Public lands planning allows for potential development of carefully sited solar and wind farms on 338,000 acres
54
Q

Vertical farming:

A
  • Practice of growing crops in stacked layers
  • Use soil free growing techniques and stack crops in specifically designed beds
  • Make use of artificial lighting and climate control to get best crop yields
  • As conditions outside become more extreme plants will struggle to survive, this ensures plants can be grown in efficient space in the correct conditions to prevent a food crisis
  • Vertical farming is worth £1.72bn worldwide in 2018
  • Japan and US leading the way but other countries are catching on
  • Edinburgh based ‘Shockingly Fresh’ has ambitions to develop 40 sites and already has 5 on the go
  • Ocado has invested £17m in the sector during 2019
55
Q

Solar radiation management:

A

-Form of climate engineering
-Aims to reflect solar rays and so reduce global warming
-Pumping sulphur aerosols into the upper atmosphere, spraying seawater into atmosphere to create white clouds and putting trillions of thin discs into stationary orbit between the Earth and Sun all either reflect the suns energy and reduce the amount of radiation reaching the planet
-However is very untried and untested and may generate unknown impacts
-It could cool the Earth within months and be relatively cheap compared with mitigation e.g. CCS
-Would need to continue geoengineering for decades or centuries as there would be a rapid adjustment in the climate system if SRM stopped suddenly
-

56
Q

What mitigation strategies can be used to rebalance the carbon cycle?

A
  1. Carbon taxation
  2. Renewable switching
  3. Energy efficiency
  4. Afforestation
  5. Carbon capture and storage (CCS)
57
Q

Carbon taxation:

A
  • By introducing taxes based on emissions, it can encourage people to make choices that will reduce their carbon footprint to avoid getting charged, or to keep taxes as low as possible
  • London Congestion Charge introduced in Feb 2003
  • Is currently £11.50 per day
  • Buses, taxis and electrical vehicles exempt to tax
  • Aim of programme was to reduce number of private vehicles entering London which will reduce the carbon emissions
  • GHG emissions were reduced by 16% from 2002 to 2003
  • By 2006, congestion in central London had been reduced by 26% since 2002 levels
  • Congestion charge boosted sales of hybrid cars
58
Q

Renewable switching:

A
  • Switching to cleaner, renewable sources such as wind, solar and nuclear will decrease carbon emissions by a large amount
  • Probably one of the most important mitigation strategies
  • A small amount of Uranium has the potential to power 500,000 homes with very little carbon emissions compared to what would be released if oil or natural gas was used
59
Q

Energy efficiency:

A
  • Study in 2014 identified Germany as a world leader in energy efficiency
  • Germany’s policies include:
  • Requiring residential and commercial buildings to reduce energy consumption by 25%
  • Subsidies to improve efficiencies in manufacturing
  • Loans to renovate older, energy-consuming properties
  • Germany’s economy has grown while still increasing its efficiency
  • Reducing consumption and making energy more efficient means less is used and therefore less needs to be generated
  • Therefore less GHG emissions during primary production
60
Q

Afforestation:

A
  • Tree cover needs to be increased for many reasons
  • Woody vegetation and the soils beneath absorb and store atmospheric carbon
  • Forests absorb approximately 10 million metric tonnes of carbon dioxide more from the atmosphere than they emit every year
  • However newly planted trees do not store nearly as much carbon as older trees and therefore it is best to prevent deforestation from occurring the first place through conservation and laws
  • Doubling the % of woodland cover in the UK from 13% to 26% by 2030 should be achievable partly through a rapid expansion of the area where young woodlands are regenerating and growing into the natural forests and wildwoods of the future
61
Q

Carbon capture and storage (CCS):

A
  • Carbon capture can capture more than 90% of CO2 emissions from power plants and industrial facilities
  • Carbon capture can achieve 14% of the global GHG emissions reductions needed by 2050 and is viewed as the only practical way to achieve deep decarbonisation in the industrial sector
  • Stored in underground geological formations
  • 2017 ADM Illinois industrial carbon capture & storage project can capture up to 1.1 million tonnes of CO2 per year. Captures CO2 from an ethanol production facility and sequestering it in a nearby deep saline formation
  • Capable of reducing SO2 emissions by up to 100%
  • Probably the most effective out of all techniques as it is tried and tested
  • However technology is incredibly expensive and developing countries will not be able to implement it
  • However the top 5 CO2 emitting countries would be able to afford and implement this technology and it is arguably more important for them to have this
  • Although top polluters will change in the future
62
Q

Business as usual:

A
  1. Emissions continue rising at current rates. RCP 8.5
  2. Temperature rise: as likely as not to exceed 4°C -> businesses impacted by climate change
  3. Sea level rises by half to one metre
  4. More acidic oceans
63
Q

Some mitigation:

A
  1. Emissions rise until 2080, then fall. RCP 6.0.
  2. Temperature rise: likely to exceed 2°C
  3. More heatwaves, changes in rainfall patterns and monsoon systems
  4. Carbon dioxide concentrations three to four times higher than pre-industrial levels
64
Q

Strong mitigation:

A

​1. Emissions stabilise at half today’s levels by 2080. RCP 4.5
​2. Temperature rise: more likely than not to exceed 2°C
3. Arctic summer sea ice almost gone

65
Q

Aggressive mitigation:

A
  1. Emissions halved by 2080. RCP 2.6
    ​2. Temperature rise: not likey to exceed 2°C
  2. Business impacted by policy change
  3. May require ‘negative emissions’ (removing CO2 from the air) before 2100
  4. CO2 concentration falling before end of century
  5. Climate impacts generally constrained, by not avoided
  6. Reduced risk of ‘tipping points’ and irreversible change